Forget the OW. Forget her. Focus on YOU. If you want to save the marriage, stop making accusations. Think about this: What are you hoping to accomplish by making accusations?
Accusations (and admissions, for that matter) accomplish nothing. Focus on improving yourself. Show him that you are prepared to be happy without him. Heck, show him you are happy now!!
Stop worrying about things that are outside of your control. If you can't control it, let it go.